1. Field of the Invention
The present invention relates to a method and apparatus for automatically welding metal frames, such as frames used in the construction of storage racks. More particularly, the present invention relates to a method and apparatus for holding frame components in a proper configuration thereof, moving the frame components past automated welders, and welding the components together to create a frame.
2. Description of the Background Art
Supportive frames, such as those manufactured by the method and apparatus according to the present invention, are known and used in industry to assemble into storage racks for storing inventory in warehouses. The preferred material, for forming frames of this type, is steel because of its strength and availability. These frames are used in multiple applications as reinforcing structural members. Among other uses, the frames form component parts of storage racks, and are assembled together to create multi-level storage rack assemblies for storing inventory in boxes, pallets, or other form thereon in industrial warehouses.
As shown in FIGS. 1 and 1A, an exemplary complete frame 10 generally includes an upper frame member 12 which is perforated with holes 15 formed therethrough along the length thereof, as shown. It should be noted that the holes 15 may be absent or present and of any desired geometric configuration, i.e., rectangular, oblong, ovate, elliptical, circular, etc.
The upper frame member 12 is U-shaped in cross-section, and is oriented with the opening 14 of the `U` facing downwardly. The frame 10 also includes a lower frame member 16 which is substantially identical to the upper frame member 12, but which is oriented with its opening 18 facing upwardly, as shown. A number of vertical cross members 20 interconnect the upper and lower frame members 12, 16 by fitting into the openings 14, 18 thereof, and are attached thereto by welding. In addition, a slanted cross member 21 is disposed between each pair of vertical cross members for reinforcement and added strength, and is oriented at approximately a 45 degree angle to the vertical cross members 20, as shown. Upper and lower ends of each slanted cross member 21 are also welded to the upper and lower frame members 12, 14 respectively.
However, the known manual method of hand building and welding these frames 10, which is the method used today, is relatively slow and is prone to human error, if an assembler does not line up the pieces right or weld the pieces together properly. This slow manual assembly results in relatively high labor costs for the hand-built frames, and this cost must be reflected in the price charged for the finished frames.
What is needed is a quicker and more reliable method of assembling the frames 10.